This study is an evaluation of the current monograph holdings of the twelve resource libraries in the TALON Regional Medical Library Program. The primary research purpose is to determine whether the TALON Cooperative Acquisitions Program (TALON/CAP) has had a measureable effect on the collections of the participating libraries. The secondary purpose is to provide objective data on current monograph holdings of both the TALON libraries and the National Library of Medicine in order to develop methodologies for continuing collection evaluation and comparisons among health science libraries. The methodology will use machine-readable records manipulated by computer to produce reports in various sequences which can be used for visual inspection and manual summarization of the data. Slight variations in bibliographic records occur frequently enough that visual inspection is necessary. The study will be valuable to all libraries concerned with collection development. It will be particularly valuable to health science librarians as the cost of medical books has increased 118.3% and the cost of medical periodicals has increased 278.6% since 1967-1969. This study will provide detailed, practically relevant information about size, overlap, distribution and shifts in the current monograph holdings of a group of health science libraries of varied size and user population and the relationship to the holdings of the National Library of Medicine.